I got quite a few bare heads, mostly 12G1316. The best way to crack check a head is to pressure check it, it always help for checking for cracks if you beadblast the head first, magnfluxing into a carbon filled exhaust port is a uselss effort. 1275 head normally are good to not be cracked, it rare to find a cracked one, but still it's not chance I take.
Here's my first piece of advice, put hardened exhaust seats in the heads, no matter what the exhaust seats look like, the old original seat even if they look good good want hold a seal, we've proved this with leak down test. Chris let me know if I can be of hlep, I got a excellent shop that does the seats, for me, in fact all the Western NC SCCA racers of all sorts of cars come down my way for this kind of work. Give me call if that interest you.
Some of you up there, probably know Tony Kipling of Old English Cars in Hendersonville, his race car, thats my old SCCA FP car, I traded him a street MGB GT he restored for the FP race car, I recently in tha last year or so helped Tony switch over to a limited prep 1275 HP engine, I did the head, crank, rods in that motor for him. Tony is a good guy, does mostly maintainence work on Ladn Rovers and LBCs you also got Gary Nye, Basicly British up there as well, he does good street car work and some restoration work, gary is good guy, ther are a few more up there, but I end my list with Gary and Tony
There00 are few BS artist up there in the hills as well
Bottom line, we've got better machine shops and engine resources down here than you guys have up there in WNC. OK, OK, Ok you guys have better roads, and colder rivers
Here's a picture of my old FP car, this was 2002 at the Mid Ohio National championship runoffs. The car pretty much looks thew same now that Tony has it.