well if you have pulled the ke70 diff out of the car have a look at the shocky mount man, that maybe 5-8mm wide holder has to support the weight of the whole of the car and deal with all the bumps and crap from everday driving, it may work for a little while till the shocky support bar thing gives in and snaps clean off the diff!!! :y:
that is why you cannot just bolt it straight up and drive on it and also the spring rates if there stiffer than stock then that will put more pressure on that bar aswell :y:
your 86 front struts will bolt straight in but will have a few dramas there has been afew guys on here that have got coilovers in there car front and rear but you will have to ask them what they did to add more support to the rear
Oh and BTW welcome to rollaclub bud :hammer: