Dashboard token value substitution

[randy_moore]

Hi  I have a input token in my dashboard for register number called $tok_reg_num$.
The customers can put in a specific number or leave it as the default of "*".   

Here's the issue,  in one of the dashboard searches I can use the default of "*"   (e..g  index=blah sourcetype=blahblah register_number=*),  in a secondary panel  I have to use a where  with a LIKE clause due to the different log type to filter the register number so * won't work and I need to change it to a  %.   

Non-working:
| Where customer="foo" AND like(Register,"*")  <--the  dashboard default for  $tok_reg_num$

I want it to be this:
| Where customer="foo" AND like(Register,"%")  <- change the $tok_reg_num$ to %

I have exhausted my meager splunk token experience in trying to get this to work. 
I can't figure out if I can examine and change it in the search  or do I need to do that  on the dashboard.   Someone give me a nudge in the right direction, please 

[justinatpnnl · Accepted solution]

Edited after I learned to read:

You should be able to use the replace function for this:

| where customer="foo" AND like(Register,replace("$tok_reg_num$", "\*", "%"))

Original Reply:

Try using searchmatch in your where statement.  It will take a regular SPL search statement and is compatible with the asterisk as the wild card.

| where customer="foo" AND searchmatch("Register=\"$tok_reg_num$\"")

[randy_moore]

Replace was the trick @justinatpnnl .    Worked perfectly.   Many many thanks!

Randy