How to remove alternator pulley?

[Warwick67]

Just got a new alternator for my Cerbie and its got the wrong pulley on it. Anyone got any good ideas to get the old one off. Its a 24mm nut, the shaft will accept an 8mm hex. Ive tried clamping a set of mole grips to the socket and fitting an allen key through where the torque wrench should attach, putting a bar on the allen key and then standing on it Just cant get enough purchase on the socket with the mole grips. I guess there is a special tool of some sort
Any tips much appreciated, I'm soooo close to getting my car back on the road

[paul.a]

I had the same problem in the end it was brute force that won

[tvrgit]

Big ring spanner on the bolt, allen key socket on the shaft, heave in opposite directions. As the above says, brute force wins the day.

[ukkid35]

Having recently borrowed a Clarke CEW1000, I reckon it could undo anything if you're patient.

[jammy_basturd]

Some I've been able to do with an ring spanner and hex key (well, hex bit and breaker bar), others I've had to use my Clarke electric wrench.

[RichV6]

Windy gun and a soft jaw clamp. After messing with various spanners and allen keys gave up
flashed up the windy (impact) gun and it took a minute to swap the old pulley onto the new alternator.