good advice above
so maybe you have the comp
Magnum 274H Hydraulic Flat Tappet Camshaft
Lift .488"/.491"
Duration 274°/296°
RPM Range 1000-7000
either the Magnum or the Extreme energy- actually 3/8 pushrods do help but you are way past that decision point this time around
"Mancini racing offers and 1.6 ratio for under $600 that is manufactured by Harland sharp that I have my eye on..."
If these are roller tip rockers then you will also need B3's shaft relocation kit- read and understand all 4 parts
http://www.b3racingengines.com/techpages/MoparRockerArmGeometry1.asp
so add a couple of hundred dollars to the cost of the rockers
Iron rockers would work just fine but you do not need them either with these chevy profile acceleration level cams and that lift
any questions you could pm Yellow Rose or post back here
IDK if edelbrock bottom taps their heads so screw in a test bolt without the shaft in each hole and measure where it tightens up/ interferes with the tap thread taper then do use that length bolt with a hard washer under the head
IDK if I would bottom tap the heads on the motor but I'd risk it if a measurement with the depth extension on your dial calipers showed a lot of depth below the bolt tighten up point which would allow a much longer bolt- did that make sense?
In a perfect world your bolt would thread all the way to the bottom hand tight
Edelbrock heads may take different length bolts than stock heads in any case-so check-- any comments guys-