Having had a chance to drive an original in the mid 70's, I knew that my SPF needed to be powered as the original. I have an original stroke 1966 428 FE in my cobra. There is a seat of the pants feeling that a true big block imparts that a small block stroker can't duplicate. Not that the 351 based cars are not as much of cobra, just different. I also have a 1967 Sunbeam Tiger, small block Ford powered. Very fast and a huge grin to drive, but does not have the tone or feel of a big block. Crane had a good fool proof method of hydraulic lifter adjustment on their web sight, now gone. This sight offers a similar method for adjustment.
http://www.scorpionperformance.com/V...MadeSimple.pdf
The key is to be sure the valve you are adjusting is well off the lobe. Rick