[clay68c10]

It would be worth pulling a valve cover and putting a dial indicator on your rocker arms to figure out your current cam valve lift specs, just to have a baseline to compare what cam you may want to change to.

Since it's a one piece seal block, look thru the pushrod and drainback holes and see if it's a block made for the factory roller setup (lots of them are). If you have a flat tappet cam in a block that has the provisions for roller it's a cheap upgrade to put the factory roller lifters in it. You could run a factory Vortec cam or HT383 cam, that would get you in a better power band for your use.

What's the chamber volume on the World heads you have? See if you can find that out and borrow/rent/buy a borescope to look at the piston tops. A lot of the new ones are video capable so you cold post a pic here and figure out what you have. Then you'll have a fair guess on CR and whether you need to do anything about it.