(1) Where under any hire-purchase agreement made after the commencement of this Act the owner is required to carry out any installation, and the note or memorandum of the agreement specifies as part of the hire-purchase price the amount to be paid in respect of the installation, the references in section 5 of this Act to one-half of the hire-purchase price and in sections 12, 13 and 16 of this Act to one-third of the hire-purchase price shall be construed as references to the aggregate of the said amount and either one-half of the remainder of the hire-purchase price or one-third of the remainder of the hire-purchase price as the case may be.
(2) For the purpose of this section the word "installation" means -
(a) the installing of any electric line or any gas or water pipe,
(b) the fixing of goods to which the agreement relates to the premises where they are to be used, and the alteration of premises to enable any such goods to be used thereon, and
(c) where it is reasonably neces