Rust/corrosion/glunk on the peddle shaft.  Maybe leaking master
cylinders have contributed to the problem. Its a remove clean check wear
and re lubricate then replace.

The pivot shaft has frozen to the pedals and is trying to rotate in
the pedal housing. The best thing to do is to pull the pedal housing
and clean everything up. It's also very important to inspect all of
the pivot points for wear. Wear creates a lot of slack in the system
which will make the clutch actuate at the bottom of it's throw. The
brake pedal, also, can be near the floor because of this.

The most common wear point is the hole where the master cylinder
connects to the pedal. These wear oval and have to either be bushed or
welded and redrilled.

This would also be a good time to inspect the master cylinders. Just
remove the lower boot and check for excessive fluid and rust.

When you reassemble the pedals lubricate everything with a good
anti-seize compound. In the UK Coppaslip, a copper based grease, here
in the U.S. most are nickle based. Use what ever is available locally.

Cheers,

Kelley