Not very.
Drain the cooling system at the bottom right of the
radiator.
Remove windshield wiper arms.
Remove the plastic cowling, then remove the crossbar.
Remove to 2 small bolts that hold the coolant tank on, and the top coolant hose from the tank.
Remove or just move some of the hoses and wires that are in the way of access to the 1/2" water hose-pipe on the fire-wall behind the left cyl. head.
This is the hardest
part. Because it is in a tight space.
There is a 1/2" hose than is connected at the bottom of the coolant tank, you can not reach it. Leave it on the tank. Disconnect it at the back of the left cylinder head. There is a hold-down clip that holds the coolant pipe to the fire-wall. The coolant hose has a spring-loaded clamp, release the clamp and slide it up onto the pipe. Now cut the hose with a knife or razor blade to remove it after 15 years on the pipe.
After the hose has been removed from the pipe pull up on the coolant tank and the 1/2" will follow as it runs behind and under the
brake booster tank.
When you buy the plastic tank the hose that was cut off at the fire-wall that hose comes on the new tank with a spring-loaded clamp. It is a formed hose. I do not know what you will get with the aluminum tank. But you will need a new hose. you may be able to hose just a straight hose BUT I never had too, so I don't know how a straight hose will fit.
NOTE:
Before I put the 1/2" hose on the coolant pipe at the fire-wall I remove the
OEM constant pressure clamp and use a worm clamp so I can tighten it with a socket with an extension. I do not have the special tool for the constant press. clamp and there is very little room behind the cyl. head.
I also put a small amount of Vaseline on the coolant pipe so the 1/2" hose slides on better.
I also use 1/2" hose grip pliers to push the hose onto the pipe.
The coolant tank has what looks like 2 top hose connections. There is only one hose connection, the other is just a blank mount to hold a rubber support.