Have en edit box in a form. Memo field

How do I position the cursor so that the user sees the content of that memo field starting with the occurence of a string of character.

For example:

Field contains

1
2
3
====
4
5
6
7
8

I want the user to see the data starting at 4 in the memo field.

I guess that SelStart and SelLengtn are involved here

But what next?