I think a reasonable deployment would be the 2 SG being stationed in the pivot point of Antelat/Msus area with the 2nd AD divisional recon unit and perhaps the 9th AIF cavalry unit the only units forward of this position. The 3 AB and 3 IMB being deployed to Mechilli so they can be supplied readily enough until the time comes move forward to support the 2SG or being the anchor on which the 2 AD concentrates. The 3 brigades of the 9th AIF being stationed at Benghazi/El Regima, Tocra and Tobruk able to withdraw onto one another.
The tiny port of Mersa AL Brega could be used partly to supply the armoured cars of the recon units. The rest would be supplied from the railhead at Misheifa in Egypt and port of Tobruk. (below)
My issue with the plan is that to commit 2AD to battle is to effectively lose it
It was a poor armor division in terms of experiance and equipment (much of it worn out) the 2nd SG was woefully understrength for the job it had to perform - The Div is particularly poor in the face of the formation it was opposing - namely the DAK based around the 5th 'Light' Division (later 21 Pz Div).
Also because of the poor condition of many of the tanks any long distance move would result in many tanks being abandoned for mechanical reasons.
The 2 Brigades of the 9th AID did not have enough transport and supporting arms - perhaps only deploying 1 Brigade of the Division and freeing up transport to allow it and the 9th AID supporting arms to act as a sort of motor Cavalry Brigade - much like the 3rd Indian
The 3rd Indian Motor Infantry Brigade was also a green newly formed formation that had only been in country for 2 months and like the other formations of Cyrcom lacked its full TO&E.
I think it is better to have fewer units with greater mobility than more with not enough.
For me its threfore move 2nd AD + 1 Brigade of the 9th AID (stripped of its transport) back to Tubruk, use the Recon assets mobile artillery engineers etc of the 2nd ArDiv + the 2nd SG to form along with 3rd Indian and 1 of the 9th AID Brigades - 3 mobile formations that can effectively act as Motorised Cavalry Brigades.
The purpose of these 3 forces + other Cyrcom recon assets is to buy time for the transport, stores/POL, dock facilities and rail/road Bridges to be destroyed while the whole force falls back onto the Frontier / Tubrok -a sort of scorched earth policy if you can use that term for Cyrenaica and the Green Mountains!
The whole purpose of the Desert force was (initially anyway) to defend Egypt and ultimately the Canal - Cyrenaica itself apart from the logistical difficulties it presents to the Italians and Germans advancing in the area is worthless.
The only danger with such a plan in my mind ...is Winston - he didn't like abandoning anything and was quite put out when Wavell (quite correctly) got his out numbered troops out of Somaliland for example.
I could quite easily see the same happening here....and Wavell coming under pressure to stand and fight with inadeqate forces.
But I can also see him doing what needed to be done regardless