Some questions about your choices of components, if I may.
The tooth wheel seems like a lot of extra complexity when you already have a spark signal from the Motorcraft distributor. You could follow the 7-pin approach described here http://www.megamanual.com/ms2/GM_7pinHEI.htm
or even use the on-board single coil spark provision on the 3.0 board.
What advantage does the Walbro pump have over, say, the Airtex E200 http://www.rockauto.com/catalog/moreinfo.php?pk=59606
and is somewhat cheaper?
I presume you will mount the Walbro pump lower than the lowest tank level, to avoid loss of pump prime?
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination ATs, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
ECO Green: '15 FCA Jeep Cherokee KL Trailhawk