building a oliver 88 engine, getting a diesel crank stroked to 4.850. still deciding on liners and pistons, i bought one liner for a case 207 diesel that is a very close match if you want a 4in bore, would just have to shim the top shoulder so it doesnt have any slop in the block and cut another oring groove in the right spot. but thinking i want to go to 4.25''. been trying to read about putting John deere 3020 gas parts in it but just wondering what someone with experience can tell me, everything i find just seems to be whispers of it and no good info. also looking for a better head off a 1650 maybe, if someone has one for sale