Some people will just sand then if they break threw in some spots thats normal and so then on the primer sealer they use an epoxy primer sealer so that they will seal and prevent rust from forming. on the style lines most people get close the them then when it's time to primer seal it they use a red scotch brite and scuff the areas they didn't sand into. Still be careful or you can still break threw if your not careful.

Mark R wrote:

Due to medical issues my Mustang has been on jack stands for 4 years. The new Exide battery was on a 'battery tender' but some how the battery swelled and blew battery acid on radiator support, battery tray, radiator, and lower frame in front. It has eaten threw paint down to primer. How do I get this painted without screwing up a $10,000 paint job and getting over spray on the chrome & aluminum engine block ? Battery was so new they gave me a new one direct exchange and I threw the battery maintainer away as it had to be flawed (1.5amp) with auto shut off & on! I don't want to have to pull engine, as I have major back issues, but that's not going to keep me from my Mustang hobby I've owned this 65 coupe since 1967, it's my baby and I'm wanting to get it back on road for my 65th birthday this October 7th. Any input would be appreciated. It's pictured in Steve's Contributors Photos. License plates are Illinois LIL HNRY it has a 408 stroker with a PA C-4 and a set of new Richmond 3:50 gears in a new Curry 9" +Trac-Lok Aluminum Housing, with 3" exhaust Dr. Gas X-Pipe and stainless 3" inlet and outlet Magnaflow mufflers. I've been clocked at 173mph compliments of a friendly Illinois State Trooper and turned a (in street trim, spare tire and all, full tank of gas and my youngest son who weighed in at 200lbs.) at Gateway Drag strip @ 11.99@116mph, which far exceeded my expectations.

Try and remove all that you can to try and make prepping the engine bay a little easier. I would use 80grit sand paper. The reason being is I would use spi epoxy on all areas that the acid got in contact with. After the sanding is completed. Follow up with a good quality degreeser. After doing that follow up with a tack cloth. Don't press the town to the surface. Lightly wipe the surface. Make sure to let the towel air out. Then you can spray the primer.  when the time come to paint the engine area. Scuff, clean, degrees, tack off, and primer seal before you apply the finish.

Mark R wrote:

Due to medical issues my Mustang has been on jack stands for 4 years. The new Exide battery was on a 'battery tender' but some how the battery swelled and blew battery acid on radiator support, battery tray, radiator, and lower frame in front. It has eaten threw paint down to primer. How do I get this painted without screwing up a $10,000 paint job and getting over spray on the chrome & aluminum engine block ? Battery was so new they gave me a new one direct exchange and I threw the battery maintainer away as it had to be flawed (1.5amp) with auto shut off & on! I don't want to have to pull engine, as I have major back issues, but that's not going to keep me from my Mustang hobby I've owned this 65 coupe since 1967, it's my baby and I'm wanting to get it back on road for my 65th birthday this October 7th. Any input would be appreciated. It's pictured in Steve's Contributors Photos. License plates are Illinois LIL HNRY it has a 408 stroker with a PA C-4 and a set of new Richmond 3:50 gears in a new Curry 9" +Trac-Lok Aluminum Housing, with 3" exhaust Dr. Gas X-Pipe and stainless 3" inlet and outlet Magnaflow mufflers. I've been clocked at 173mph compliments of a friendly Illinois State Trooper and turned a (in street trim, spare tire and all, full tank of gas and my youngest son who weighed in at 200lbs.) at Gateway Drag strip @ 11.99@116mph, which far exceeded my expectations.

 WOW!!!  with a 3.5 rear end, C-4 transmission your 408  pushing a 66 coupe should be spinning at 7825 RPM at 173 MPH with 26 inch diameter tires.
That is a very impressive engine.
 I'd like to see the specs on that build. Also curious as to the type of tires on the car and the speed rating.