Hi guys, thanks in advance for any help you deliver!

I have a few small jobs to do on a recent car i've acquired, a 99 uk turbo.

Firstly, the boost gauge and all vacuum hose has been removed, do I need to block off the nipple on the inlet or can I leave it as it is?

Secondly, the oil pressure gauge has been removed, I have brought a new sensor, can I just block the whole off with the sensor, or do I need to re-wire it up?

Lastly and Ill be lazy, as the car is miles away from me as Im at work, what size are the large alternator bolts? M8x125?

Thanks

p.s, i have had a scout through search btw