[Roadsters] Newbie

[Mark Zitterich]

Hello,
I'm probably the newest Roadster owner.  It arrived last night and I
registered it today.  This is my first roadster (1968 SRL-31102879).  It's a
bit of an omelette (someone dropped a R-1600 in it and it has 1969 front
fenders), but I'm looking forward to it,  My last Datsun was a 73 240Z that
was great fun until an untimely crash with my roomate driving it.
I have a
couple of questions, since I have not acquired a service manual yet.
1.  Does
the gearbox (4sp) and differential take 75W-90?
2.  Is there an aftermarket
electronic ignition system available?  Would it work for the R-1600 and a
U-2000 if I decide to go back to a 2000cc engine?
3.  The oil pressure and
fuel guages work, but not the temp?  Where is the temp sender located?  I
looked on both sides of the radiator, but couldn't find one or a hole for one.
4.  What is the toggle switch on the left side of the steering wheel for?
5. 
Is there a Roadster club in Colorado?  I'm just north of Colorado Springs.
Thanks,
Mark