Coldstart,

I totally understand the fear and unknown part of the process...It is also falacy of the tools costing many dollars...Only five special tools are needed. The rest are sockets. Torque wrenches

A)Depth vernier caliper to read in MM and inch. The standard size will work, but a 10" one will be best

B)large feeler gauge

c)small PIC set.

D)few large bolts and small blocks of wood

E)3" PVC drain coupling(see the link below how all is used. You will use this on four clutch packs.This is how to fix reverse seal which is the small seal)

722.5 transmission oil pump rebuid DIY - Mercedes-Benz Forum

For reverse, you need to open it up, and it is up near the front, but the forward gears YOU may have a chance with the valve body, B1 and B2 piston.

Most transmissions in the junk yards(at lease on the WEST) have reverse issues. Look at this thread as I just have said all of this . I have the service manuals to this tranny if you need them, just PM me as they are to large to post. We can exchange emails. I also have hundreds of photos of each rebuild I do I can email you a packet, so you get the feel of what it takes.If it something you are willing to do, walk away from?

http://www.peachparts.com/shopforum/tech-help/348463-300te-722-358-tranny-3rd-4th-gone.html

A rebuild kit for this is at $180 all day with all clutches. I'd recommend changing a few other parts, B2 piston, some big washers, and plastic parts.

When you say you lost all forward gears? all of them? or first or second will not engage? look at the troubleshooting section of this thread

http://www.peachparts.com/shopforum/3267106-post13.html

It is not magic....it is a bunch of seals and clutches that go bad on the 722.3-722.5. The 722.6 is a different animal as that one get expensive to fix, but quicker to rebuild in time.

Look at post 17 on the thread above.The document has lots of meat info.

Lastly, I have a transmission jack that is worth its money in gold, and it is 80USD...

Transmission Jack - 450 Lb. Capacity

B1 piston is the hard to remove and install, and I made my own tool with a electrical plate and metric bolt...

The rest requires patience and accountability(physical and mental). Walk away when you feel pressure in your daily life.

Martin