I am with you Big Tom. I have Truck Rally's too and just bought a repop set of stock centers off ebay.
I am thinking about cutting the center portion down so it doesn't stick out as far. Basically cut off the cap, turn the hub down, and re-attach the cap. But I haven't convinced myself that is the look I really want.
Also considered making an adapter that bolts to the stock rim to accept different centers.
Keep lookin', I'll do the same. If we find anything report back.
John