Not a hard job. Make sure you replace the upper seal - #44, the lower seal - #28, and two orings - #32.
Take the hydraulic block apart and clean any rust and crud out of it. Lube with light grease or heavy oil when you reassemble.
You will need an I&T FO 20 manual to correctly adjust the spring washer - #42 when you reassemble it.
Many people have trouble getting the right plungers in the right holes.
As per the photo below the special plungers with the horns go into the hole marked by the pencil.
Notice the extra fitting is on the top, right side of the block.
You can install the plungers after you set the hyd block back on the column. Install one special plunger horns up, then two balls, then the second plunger horns down. All other holes get a plunger, then a spring, then another plunger. No top or bottom on those.
You can call your dealer and get the seals. They are not expensive.
Part numbers are:
Upper seal - 83929295
Lower seal - 86531349
o rings - 1707280