I am going to try an hybrid Mu follower (aka Moglia Gyrator)for an ECC88. And I need some help, please.

I read on Ale's site the formula is 1/Gm. Is Gm the Mu of the tube? So here 33 which gives 1/33=0.0303,equal to 303 ohms or something else ?

About the littler J-Fet I saw the use of the J310 (I go diy and use To90 for factor, not soic) and the choice what about the mA you need, is it about the anode curent limit of the tube anode for the Jfet choice ? How to choose this J-fet please ? (J310, BFA245A, J113... I have few on hands)

How about the last flavor of the big Mosfet today and how much volts the circuit has to drop to work fine - anode will go with around 75V-.