It's been a while but I go for:
Top Left - ACRV M-1979 (2)
Top Right - ACRV M-1974 (1)
Bottom Left - 2S3 sp 152mm and Zil-131 truck
Bottom Right - East German IMR
Yes. 3 Sov bits of Arty kit (I'd call them ACRV 2 on a BTR, ACRV 3 on a MTLB chassis , 2S3 and a Zil 131). We remembered the East German sapper gear IMR with the moniker 'I Move Rocks', looks like a T-55 chassis.
As you say, it's been a while. Still remember most of this stuff but have forgotten what I had for supper last night.