[Roadsters] 2Q's. Which Chevy water pump pulley and what Crank Pulley Oil seals?

[Walter Peterson]

Replacing the stock 1600 water pump pulley with a Chevy version, what model
& year do I get?
Apparently this is the preferred method to enable a fatter belt.
I've got a 280-Z Alternator & a new Rebello (L24-L28) Crank Pulley, both of
which want a bigger belt than my stock 1600 can tolerate.
A spiffy Aluminum pulley would add speed just by looking at it.  :)

Also the Rebello Pulley has the same ID as my Roadster crank, but needs a
larger ID oil seal to accommodate the Z-sized seal landing.
I roughly measured the stock seal OD at 2.7" the old ID was 1.7XXX", the New
ID needs to be ~1.90".
Someone must have been done this before.

Thanks,

Walt Peterson
Santa Barbara CA
67e R20 w/44's
5-spd, LSD & Big Brakes.