I've got an 85 L69 with a cracked head (should be 58cc) and the only replacements I've found within reasonable budget are all 65cc. part #ATK 2C05 from NAPA https://www.napaonline.com/en/p/ATK2...pressionRank=1

What I need to know is if those would work with minimal modification and what I would need to do to get them working. I'm already figuring that I would need to replace both heads to maintain even fuel flow and since the chamber size is increasing and my compression ratio is dropping anyway should I still worry about needing a thin head gasket like the Felpro 1094, or can I get away with a Felpro 8510

I'm just wanting to get it running good for a couple summers driving while I save and decide if I want drop a 383, LS3, or keep the original drive train.

 

Look for a reman 416 head.

 

Look for the cylinder head casting number on the head under the valve cover.. It will end in either 4416 or 601.. Call or visit your local automotive rebuilder/ machine shop.. The will very likely have this re-buildable 305 head core or may even have it all ready rebuilt ready to install.
Yes you can use the felpro 1094 steel shim head gasket as a replacement for the oem factory 305 steel shim head gasket (that you cannot get)

You can rebuild one or both heads. your call.
These 305 ho heads are common.
Tins of exact replacements.
You may even find a good running used 305 engine with the same heads.. $50-$100
Kijiji Craigs List , Facebook Marketplace. etc

 

Yours are casting # 416. VERY common. Shouldn't be any problem at all to find. Check your local machine shops.

 

Thanks for the advise, I'll start looking for a local shop for the head then.