Aiwa AD-R470, auto reverse deck problem

I'm in the proccess of trying to get the above dual capstan deck working again.
It was in a dirty filthy state when I got it, thick black grease all over the transport (Aiwa  X3) an old rubber band in place of the main drive belt which was routed around the TU and Supply capstans so they turned in the same direction!
Anyway the transport and inside the deck has cleaned up quite nicely (took hours) and looks as though it should function once the correct drive belt arrives and is routed around the dual capstans correctly.
Whilst measuring the size of drive belt needed I've noted the auto reverse head wasn't
swivelling through 180 degree when moved manually, as it should. Discovered the small white gear on the back of the head was missing almost half. Dismantled the back of the head, retaining spring removed, broken gear removed.
Unable to repair the gear, the missing section isn't inside the deck, surprised to find two sources that can supply a replacement gear which I'm waiting on.
Problem I now face is that the screened cables for the EH, PB and REC heads all pass through the centre of the offending broken gear and they all go to a 9 pin connector.
The hole in the centre of the gear is under 3mm in diameter so there's no way to pass the cables let alone the connector through the opening.
I don't want to disturb the head itself as I'm sure it will not function correctly afterwards. So I'm left with cutting either the 9 very short and tiny wires that emerge from the back of the head and trying to join and resolder them or cut and stagger the 3 screened leads and then repair these.
Anybody here had similar problems and if so how did you tackle getting the repair done? Any advice thoughts or idea's appreciated and accepted.