How Do I Get the A/C Evaporator Out

[Scope9]

I’m in the process of re-doing the A/C system on my ‘68 and have searched everywhere for info on how to remove the evaporator/blower assembly from inside the car.  It is a Kuhlmeister unit.  Despite removing just about every bolt and screw I could find, the thing remains solidly in place. 
I’d be grateful if someone could advise me on where the fasteners are and how to remove the unit.

[Peter]

I have a frigiking, on the underside are four holes via which you can reach the screws. Maybe the same with yours.

Peter

[BobH]

There are many old posts on this subject if you search, use the search button top left of the page

this post was regarding a 230SL, but may be the same for yours

https://www.sl113.org/forums/index.php?topic=21485.0

Perhaps you can contact the members who posted this and see if they figured it out?

[johnk]

I just installed one and the only screws I could find that needed to be used where the ones above, the right kick panel and the blower mount in back.

[Scope9]

Thanks for the kind advice folks—much appreciated.  The complication I discovered was that the last two screws securing the unit are rather diabolically hidden, requiring that the small “knee vents” at the bottom of the unit be removed to get at them.  The other two are accessed through the plastic capped openings nearby.
Just to make things a bit more interesting, one screw head had been snapped off and the other three all were different sizes with different heads.  The dealer-installers probably shouldn’t have been working for Mercedes.
The unit is out and I appreciate the guidance.