A custom is really the only way to go but I am fortunate enough to have a local covertor shop that builds them for around $200 up to $500 for a billet with anti ballon plates.The problem with off the shelf is they are a one size fits all and have cheap parts and a stall rating based off an avearge 350 h.p. chevy 350,thats why they have an identical advertised stall for all covertors regardless of make.Find out where your foot brake stall is at and the flash and see if its where it needs to be,I would want at a 2,500 flash with setup and around a 2k foot brake minimum.Also check to see what rpm your going though the traps then you can use an online claculator to see how much slip is in the convertor,if these check out I would look elsewhere for benefits in the suspension.