the holes in the rim should be the diameter of the lag bolts.

A long-winded reply here but useful to understanding the parts 'system'....in my opinion, I'd recommend (and have done it) to drill the lag screw holes at least or about 1/16" larger diameter than the lag screw diameter....
....why?....first, the fretboard must align level to the head when all the parts are tightened up.
Second, unless you're extremely, extremely precise and can dial in the alignment of your drill bit to only several thousandths of an inch deviation from being perfectly located and drilling true, then without much doubt your fretboard WILL NOT be perfectly level.
Third, if the fretboard is not perfectly level relative to the head then usually just a little twist or 'rotation' of the neck/heel is enough to get the desired level fretboard alignment.
Fourth....but won't there be some loose 'slop' in the heel fit if the lag screw hole is larger?...answer - no, because this brings up the concept of 'parts seating'.
Wha?....wood parts and lacquer finishes (or urethane, or 'bout anything) will compress and/or flow when all the nuts and bolts are snugged up - in fact, this compression and flow makes the parts 'nest together' in intimate contact - thus 'seating'. Excellent for transmission of vibrational energy.
Fifth, over time, due to the flow and compression - plus the wood 'shrinkage' due to age and loss of humidity/moisture - banjo parts need to be snugged-up once in a while. (....an obvious and telling clue is loose tuners).

Now, you have to keep in mind that it's necessary to have an excellent fitting heel cut to start with but you will still maintain that even though the over-sized lag screw holes allow you to 'twist' the neck a few thousandths to seat the FB at level. Sometimes a neck needs 'twisting' by 1/64" or 1/32" to be level but depends on how keen your eye is.

Lastly....note, when I say 'level fretboard', of course the fretboard is not truly level with the head but eyeball the 'in-plane' level-ness (say, of the FB at the 22 fret) relative to the head (and not the tension hoop). And, over time your parts will be friends with each other.

I hate to keep doing this, but it's necessary

Here's a diagram of two versions of dual coordinator rods (the rim hole just clears the hanger bolt) and an import single rod (rim hole clears the coordinator rod).  Though the import design "works", it is an inferior mounting method in my opinion.

Thanks fellows this is all great information I can use.

Seems I recall the hanger bolts come with your dual coordinator rod package.

Brett hanger bolts did come with coordinater rods. I'm at the point of installing bolts in the neck at correct angle and placement. Been working on this thing since January, after work, learning as I go. Hope to build another so this one is my "learn from mistakes build". Really enjoyed the process though!