What gearbox do I have?

[Speedy Gonzales]

Ive had my manual 4 speed gearbox taken out of my cobra and had a LT77 5 speed fitted. Im probably gona sell the old 4 speed and was wondering if anyone can correctly identify it for me.
The following sets of numbers and letters are found on the box.

Top of bellhousing - WYF
E624
591357
Side of gearbox casing (some are a bit of a gues due to wear) - A.D.C 1
594757
81
On the inside of the bellhousing just above the input shaft - 540891
20

The only other information I have is that it was originally mated to a 3.5 rover from the 70's and may have came from the same donor also the bellhousing can be detached but it seems as though it is part of the gearbox.
Any ideas anyone?

[Clarkson]

Some pics would be real nice!

[Speedy Gonzales]

I took these ones this morning after I degreased it hope they help.

[dave]

No expert but is it a Rover P5 or P6 4 speed?

[Rat Boy]

Rover P6 3500S

[ants427]

Definatly Rover 3500cc Gearbox, cant say if it is p5 or P6.

[Speedy Gonzales]

Im pretty sure that the original engine came from a P6 do it would fit that the gearbox came from the same car, just needed it confirming, dont want to flog it as something its not, thanks all.