Marking on exchange engine, 30 hp

I am wondering if i can use this engine in my -51 split. I would like to know what all this markings tell about the engine. Take a look at both pictures  around the engine number there is a lot of signs.
P=
A=
4W=
0268=
the round marking on the right.
O=
0126=
One the right side of the sokcet :
010947X`=

No doubt that this is an exchange engine. The markings are probably used during the renovation-
I wil say tahnk you for help in advace.

Hello again Jens,
I can't explain each number but for one or another I have an explanation:

P=?
A= Two explanations:
1.: Sign for an exchange engine letter "A" stands for "Austausch", in use sometimes in the 50s
2.: Sign for the engine type after 1965: A=30PS. This sign were used after the engine were renewed in the exchange factory after 1965, additional to the sign for exchange (X or VW with double arrow in a circle)
4W=?
0268= maybe an employee number in the quality department? 
the round marking on the right. ?
O=?
0126= maybe another employee number in the quality department 
On the right side of the sokcet: 010947X`= The number of the exchange engine. Normally after 1968 the old engine number were removed and a new number were stamped  into the field for the engine number. But if the engine belongs to a car in foreign countries (in your case in Norway) it could be possible that the old number stays in place and the new number were marked as shown in your picture (on the left side of the generator base). Because of export / import tax reason.

Best regards,
Jens

Thanks Jens.

your answer is probably close to the truth . I also think that the P explain that the case hakves was planed before  line bor.