No manual tranny bolts up to the vh45de, however there are a few adaptor plates out there to fit it to the Z32 tranny and I think theres one for the mk3 supra tranny.
All vh motors had timing chains, the earier U.S. versions (90-93) had a single chain and the later versions and JDM vh41he's had dual chain set ups. The earlier vh45 had sodium filled valves, vtc (through 95, in 96 it couldn't meet emissions and was dropped), and more aggressively tuned ECUs too. So and earlier motor will put out a bit more power than the newer motors (like BRAPPs.) Oh, and the vtc was activated below 4600 rpms, so it doesn't have that much of an affect on the top hp, but gives the older motors two hp peaks.
I may had been guessing too much about weight difference, but I still can't find a verifiable figure for the vg. I still think that the vh is lighter, maybe not by much, but at the least they're about the same weight.