Don't worry about the HP rating.
Those 68 WT's are great engines with big valves, screw-in studs, and guideplates.
Same engine layout as the 69 and 70 WT rated with 350hp.
H-O had better manifolds and i think a tad lil more bump on the cam maybe.
But all else the same.
Might be worth while to ask if they lowered the compression ratio any, or used hardened seats. Forged pistons, bored oversize, etc
Cam Card or Cam Specs
In case you missed it in this other thread , here is what the transmission stampings will look like for reference.
The Trans Unit Number from your BHC and partial VIN
