It's not uncommon for machine shops to take a flat punch and tap down where the caps and registers meet to tighten up the cap fitment when a block is align honed. Sounds like it might help yours out if you planned that operation for your block....
There is already a half a dozen or more Slant intakes that are EFI ready, Clifford's and all of Aussiespeed's. Gill does nice work, it'll be interesting to see what comes for this....
You need to verify the notch on the balancer accurately corresponds to true TDC before you do anything else. The rubber ring can deteriorate over time and cause the outer ring of the balancer to slip on the inner hub. If the timing mark on it no longer accurately aligns with your timing pointer...
Since Gill is in the business of modifying intakes for EFI, it seems counterintuitive on his part to partner with a company that can effectively make products that takes away his business.
I've looked at adapting several different factory thrust plates from other engines and it's very doable with little effort. The cam gear will need to be clearanced to create the end play, but its a minor thing. No roller bearing thrust button will be needed if you use a plate....
Not knowing your final goal for HP, its difficult to make suggestions. But you should install better fasteners in the rods, mains and head. Several guys on .org have had parts failure in their bottom ends(stock connecting rods) even with ARP rod bolts at the 300-ish HP level. So Molnar rods may...