Hi Steve.
Depends on which model and version...
I have a Sierra based Classic Replicas from about 1998 and the rear suspension mounting cuts the back corner off the floor pan under the seat. I modified the seat so it fits around this but it is still quite tight in there and I'm not tall.
You might need to change the seat completely for one with less padding and frame...and my seats are bolted to the floor!
The other other thing to do is remove material from the dash either side of the wheel to allow space for your knees.
Don't be afraid to pop the seat out and take a look underneath!?
Declan
RV8, Sierra based Viper.
I'm sure if I give it enough love it will, someday, love me back!?
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